This invention relates to a marine propulsion system and more particularly to a combined engine and transmission control for such a propulsion system.
As is well known, watercraft, unlike motor vehicles, generally do not have a braking system. Therefore, it is a fairly common practice for the operator of a watercraft to slow the direction of travel of the watercraft by shifting into a drive mode opposite to that in the direction the watercraft is traveling. This may be done for braking from either a forward drive mode or a reverse drive mode.
Generally, watercraft employ a system for control of the engine and watercraft propulsion system referred to as a "single lever control". Such single lever controls comprise a single control lever that is connected via a motion transmitting connection or in some other way to both the speed control and the transmission of the marine propulsion system.
The operation is such that in a neutral position, the transmission is held in neutral and the engine is maintained at its idle speed. When the control lever is shifted in one direction or the other from neutral, the transmission is first moved into engagement to respective drive condition while the engine is maintained at idle. If the operator continues to move the single lever control in the same direction then the throttle is progressively opened but only after the shifting has been completed.
This is a very effective control and is very useful to the operator. However, this type of system has certain disadvantages when the transmission is utilized to brake the travel of the watercraft. That is, if the watercraft has been traveling in one direction at some substantial speed and the transmission is shifted into neutral, the watercraft will continue to move in that direction and the propeller will be rotated or driven in the same direction it was previously by the drag of the water. The engine speed will also be returned to an idle speed.
Thus, when the operator attempts to immediately engage the transmission to drive in an opposite direction to obtain a braking effect, there will be a relatively high load placed on the engine since it must overcome the drag on the propeller to reverse its direction of rotation. When operating at idle speed, this drag may be sufficient to cause stalling of the engine. This obviously is not a favorable situation.
It is, therefore, a principle object of this invention to provide an improved transmission and throttle control for a marine propulsion system.
It is a further object of this invention to provide a control for a watercraft transmission and engine wherein stalling when utilizing the transmission and engine as a brake will be prevented.